Voice and data networks used by enterprises may feature routers and other devices with ports that receive and pass transmissions to users. Routers contain software and hardware that may be customized to the tasks of routing and forwarding a variety of packet types. Routers have multiple network interfaces, which may be to different physical types of networks and to networks that observe a plurality of different networking standards. Besides making determinations about which interface a packet is forwarded to, a router also manages congestion, when packets arrive at a rate higher than the router can process. Routers may use policies to manage traffic and reduce congestion. Routers may provide connectivity inside enterprises, between enterprises and the Internet, and inside internet service providers. Enterprises that are widely distributed with few or no central locations may subscribe to Wide Area Network (WAN) services hosted by telecommunications service providers. Such providers may offer managed Internet Protocol (IP) solutions that may integrate voice and data infrastructures. The solutions may segment user traffic across the provider's network backbone and isolate individual customer networks completely from each other.